Paging systems are well known in the art. The paging systems operate wherein a calling party sends a message to the control station or clearing house which then transmits the page to the pager apparatus. The pager apparatus receives a signal resulting from the call and includes an audio and/or visual indicator associated with it to inform the called party that he has been paged. In some paging systems, a numeric field such as the telephone number of the calling party is displayed on the pager apparatus. In others, limited messages can also be transferred from the calling party to the called party through the central station.
Generally, the individual placing the call is referred to as the caller, and the individual holding the pager apparatus as the called party. Paging apparatus differ from telephone equipment in that pagers can only receive remotely transmitted signals and alert the called party but they do not have the capability of transmitting responses. Thus, they cannot support real time, two-way communication. Hereinafter, reference to a pager, pager apparatus or receiver, refers to a receive only device of this type.
Various paging systems have been well known in the art. By way of example, U.S. Pat. No. 4,172,969 issued to A. B. Levine describes a paging system wherein a transmitting station automatically receives and transmits limited content coded signals from a caller, and automatically sends out messages to remotely located receivers. The pager receivers include a video display panel for displaying messages, and a memory for storing the messages for later retrieval and display.
U.S. Pat. No. 4,263,480, issued to A. B. Levine, further improves the aforementioned invention by expanding the size and scope of the transmitting station to comprise a central broadcast station capable of serving a large number of subscribers at greater distance from the station. It also provides completely automated operation in paging subscribers and transmitting messages thereto in response to a large number of callers. The pager receiver described by Levine requires that the station include an automatic answering device for instructing a telephone caller to dial an alpha-numeric address that selects one of the pager receivers and additionally instructs the caller to dial a further alpha-numeric limited content message to be transmitted to the selected receiver.
U.S. Pat. No. 4,618,860, to Toshihiro Mori, describes a radio paging method for use in transmitting radio call signals from a subscriber's substation through a base station to pager receivers in the form of a radio call signal, the message information is divided into a plurality of species to which key codes are assigned, respectively. The radio paging method described therein provides for rapid transmission of a wide variety of message information without the need for special input devices. Thus it is possible to increase greatly the calling rate in each radio channel. It also provides for drastic reduction of reception sensitivity at each pager receiver despite a substantial increase in transmission rate.
U.S. Pat. No. 4,706,272 to Nishimura et al provides for a paging communication system adapted to transmit an individual calling code from a base station to a plurality of receivers assigned to a particular group number. This invention circumvents the problem of conventional paging systems that are unable to inhibit information to a particular receiver within the same group. Furthermore, this invention inhibits information to those receivers that have as yet no renewed contracts for using the communication system by paying due rental fees.
While such paging systems have attempted to provide improved features, thus far, paging systems have not been able to provide a system that can be universal with pager use by each and every individual and yet individualized for selective features. Also, thus far, there has not been provided a system wherein the caller is billed for the call rather than the called party.
Additionally, typical paging systems include a central station which does little more than serve as an information transmission facility. Such systems may provide switching, forwarding or routing of the paging call. The call is initiated by the caller and the central station transmits the page to the called party. If the central station is in the nature of an answering service or a secretary, they can select which calls get through, but such selectivity is achieved by secretarial decision and restriction and not through automatic implementation of selection criteria established by the called party. Furthermore, there is no response given to the caller to assure him that the page has in fact been transmitted.